It is proposed that different types of semiconductor components are integrated into a single chip to reduce size of a semiconductor device while increasing its functions. This kind of IC is called a hybrid IC. The different types of semiconductor components may be a complementary metal-oxide semiconductor (CMOS) transistor, a bipolar transistor, and a laterally diffused metal oxide semiconductors (LDMOS) transistor. The CMOS, bipolar, and LDMOS transistors are digital, analog, and power components, respectively.
In the hybrid IC, a trench isolation structure is applied for providing isolation by trenches among the components to reduce malfunctions due to electric interference. A silicon on insulator (SOI) substrate is used in the hybrid IC and the trenches are formed in the SOI substrate.
During the manufacturing process of the hybrid IC, the area of the SOI substrate is divided into regions by the trenches. Then, CMOS, bipolar, LDMOS transistors are formed in respective regions. The electric interference among semiconductor components can be reduced by using the SOI substrate and the trench isolation structure.
However, the hybrid IC requires a long testing period because it has various types of semiconductor components integrated in a single chip. Manufacturing processes of the semiconductor components, which are different from each other, become more and more complex due to an increase in variety of the semiconductor components. As a result, the testing period of the hybrid IC becomes even longer, and therefore the development period of the hybrid IC becomes longer, increasing the development cost.